rc ?

Je ne peux pas vous assurer que c'est par ce moyen que base-config est lancé, mais dans /etc/init.d/rc il y a quelques parties qui devraient vous interesser :

if [ S = "$runlevel" ]
then
#
# See if system needs to be setup. This is ONLY meant to
# be used for the initial setup after a fresh installation!
#
if [ -x /sbin/unconfigured.sh ]
then
/sbin/unconfigured.sh
fi
fi

if [ S = "$runlevel" ]
then
#
# For compatibility, run the files in /etc/rc.boot too.
#
[ -d /etc/rc.boot ] && run-parts /etc/rc.boot

#
# Finish setup if needed. The comment above about
# /sbin/unconfigured.sh applies here as well!
#
if [ -x /sbin/setup.sh ]
then
/sbin/setup.sh
fi
fi

Bonne chance !